Core Dimensions of Anxiety and Depression Change Independently During Adolescence

The developmental trajectories of emotional disorder symptoms during adolescence remain elusive, owing in part to a shortage of intensive longitudinal data. In the present study, we charted the temporal course of the tripartite model of anxiety and depression-which posits an overarching negative affect dimension and specific anhedonia and anxious arousal dimensions-over adolescence and emerging adulthood to construct a developmental map of the core dimensions of emotional disorders. We recruited 604 high school juniors, overselecting those at high risk for emotional disorders, and assessed the tripartite symptom domains 5 times annually. Latent curve modeling revealed that negative affect and anxious arousal declined over follow up, whereas anhedonia did not. Moreover, the correlation in rate of change varied across pairs of symptom domains. Change in negative affect was moderately correlated with change in anxious arousal, but change in anhedonia was not significantly related to change in any other domain. Symptom trajectories, and the pattern of covariation among trajectories, were equivalent across gender and comorbidity status. We discuss implications of these findings for developmental models of anxiety and depression, as well as transdiagnostic frameworks for emotional disorders

Pathological Personality Traits and the Naturalistic Course of Internalizing Disorders Among High-Risk Young Adults

BackgroundA personality disorder diagnosis signals a negative prognosis for depressive and anxiety disorders, but the precise abnormal personality traits that determine the temporal course of internalizing psychopathology are unknown. In the present study, we examined prospective associations between abnormal personality traits and the onset and recurrence of internalizing disorders. MethodsA sample of 371 young adults at high risk for internalizing problems completed the Schedule for Nonadaptive and Adaptive Personality-Second Editiona measure of 12 abnormal personality traits and three temperament dimensions (i.e., Negative Temperament, Positive Temperament, Disinhibition vs. Control)and underwent annual diagnostic interviews over 4 years of follow-up. ResultsIn multivariate survival analyses, Negative Temperament was a robust predictor of both new onsets and recurrences of internalizing disorder. Further, the Dependency and Self-Harm abnormal personality dimensions emerged as independent predictors of new onsets and recurrences, respectively, of internalizing disorders after statistically adjusting for variation in temperament. ConclusionsOur findings suggest that abnormal personality traits and temperament dimensions have complementary effects on the trajectory of internalizing pathology during young adulthood. In assessment and treatment settings, targeting the abnormal personality and temperament dimensions with the greatest prognostic value stands to improve the early detection of enduring internalizing psychopathology

Core Dimensions of Anxiety and Depression Change Independently During Adolescence

The developmental trajectories of emotional disorder symptoms during adolescence remain elusive, owing in part to a shortage of intensive longitudinal data. In the present study, we charted the temporal course of the tripartite model of anxiety and depression-which posits an overarching negative affect dimension and specific anhedonia and anxious arousal dimensions-over adolescence and emerging adulthood to construct a developmental map of the core dimensions of emotional disorders. We recruited 604 high school juniors, overselecting those at high risk for emotional disorders, and assessed the tripartite symptom domains 5 times annually. Latent curve modeling revealed that negative affect and anxious arousal declined over follow up, whereas anhedonia did not. Moreover, the correlation in rate of change varied across pairs of symptom domains. Change in negative affect was moderately correlated with change in anxious arousal, but change in anhedonia was not significantly related to change in any other domain. Symptom trajectories, and the pattern of covariation among trajectories, were equivalent across gender and comorbidity status. We discuss implications of these findings for developmental models of anxiety and depression, as well as transdiagnostic frameworks for emotional disorders

New records of Burgess Shale-type taxa from the middle Cambrian of Utah

Cambrian strata of the Laurentian craton contain numerous examples of Burgess Shale-type faunas. Although displaying a more or less concentric distribution around the cratonal margin, most faunal occurrences are in present-day western North America, extending from the Northwest Territories to California. Nevertheless, the soft-bodied and lightly skeletalized fossils in most of these Lagerstätten are highly sporadic. Here, we extend knowledge of such Middle Cambrian occurrences in Utah with reports of four taxa. An arthropod from the Marjum Formation, Dytikosicula desmatae gen. et sp. nov., is a putative megacheiran. It is most similar to Dicranocaris guntherorum, best known from the younger Wheeler Formation, but differs primarily in the arrangement of pleurae and overall size. Along with a specimen of ?Yohoia sp, a new species of Yohoia, Y. utahana sp. nov., is described. It differs from the type and only known species, Y. tenuis, principally in its larger size and shorter exopods; it is the first description of this genus from outside the Burgess Shale. A new species of a stem-group lophotrochozoan from the Spence Shale, Wiwaxia herka sp. nov., possesses a palisade of dorso-lateral spines that are more robust and numerous than the type species of Wiwaxia, W. corrugata. Another notable taxon is Eldonia ludwigi from the Marjum Formation, which is interpreted as a primitive ambulacrarian (assigned to the cambroernids) and a new specimen of the ?cnidarian Cambrorhytium from the Wheeler Shale is illustrated

Self-avoiding walks and polygons on the triangular lattice

We use new algorithms, based on the finite lattice method of series expansion, to extend the enumeration of self-avoiding walks and polygons on the triangular lattice to length 40 and 60, respectively. For self-avoiding walks to length 40 we also calculate series for the metric properties of mean-square end-to-end distance, mean-square radius of gyration and the mean-square distance of a monomer from the end points. For self-avoiding polygons to length 58 we calculate series for the mean-square radius of gyration and the first 10 moments of the area. Analysis of the series yields accurate estimates for the connective constant of triangular self-avoiding walks, $\mu=4.150797226(26)$, and confirms to a high degree of accuracy several theoretical predictions for universal critical exponents and amplitude combinations.Comment: 24 pages, 6 figure

Enumeration of self-avoiding walks on the square lattice

We describe a new algorithm for the enumeration of self-avoiding walks on the square lattice. Using up to 128 processors on a HP Alpha server cluster we have enumerated the number of self-avoiding walks on the square lattice to length 71. Series for the metric properties of mean-square end-to-end distance, mean-square radius of gyration and mean-square distance of monomers from the end points have been derived to length 59. Analysis of the resulting series yields accurate estimates of the critical exponents $\gamma$ and $\nu$ confirming predictions of their exact values. Likewise we obtain accurate amplitude estimates yielding precise values for certain universal amplitude combinations. Finally we report on an analysis giving compelling evidence that the leading non-analytic correction-to-scaling exponent $\Delta_1=3/2$.Comment: 24 pages, 6 figure

Exceptionally Preserved Jellyfishes from the Middle Cambrian

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (∼505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish taxa. These new discoveries may provide insight into the scope of cnidarian diversity shortly after the Cambrian radiation, and would reinforce the notion that important taxonomic components of the modern planktonic realm were in place by the Cambrian period

Skeletal Muscle Regeneration and Oxidative Stress Are Altered in Chronic Kidney Disease

Skeletal muscle atrophy and impaired muscle function are associated with lower health-related quality of life, and greater disability and mortality risk in those with chronic kidney disease (CKD). However, the pathogenesis of skeletal dysfunction in CKD is unknown. We used a slow progressing, naturally occurring, CKD rat model (Cy/+ rat) with hormonal abnormalities consistent with clinical presentations of CKD to study skeletal muscle signaling. The CKD rats demonstrated augmented skeletal muscle regeneration with higher activation and differentiation signals in muscle cells (i.e. lower Pax-7; higher MyoD and myogenin RNA expression). However, there was also higher expression of proteolytic markers (Atrogin-1 and MuRF-1) in CKD muscle relative to normal. CKD animals had higher indices of oxidative stress compared to normal, evident by elevated plasma levels of an oxidative stress marker, 8-hydroxy-2' -deoxyguanosine (8-OHdG), increased muscle expression of succinate dehydrogenase (SDH) and Nox4 and altered mitochondria morphology. Furthermore, we show significantly higher serum levels of myostatin and expression of myostatin in skeletal muscle of CKD animals compared to normal. Taken together, these data show aberrant regeneration and proteolytic signaling that is associated with oxidative stress and high levels of myostatin in the setting of CKD. These changes likely play a role in the compromised skeletal muscle function that exists in CKD

Trends in the sources and sinks of carbon dioxide

Efforts to control climate change require the stabilization of atmospheric CO2 concentrations. This can only be achieved through a drastic reduction of global CO2 emissions. Yet fossil fuel emissions increased by 29% between 2000 and 2008, in conjunction with increased contributions from emerging economies, from the production and international trade of goods and services, and from the use of coal as a fuel source. In contrast, emissions from land-use changes were nearly constant. Between 1959 and 2008, 43% of each year's CO2 emissions remained in the atmosphere on average; the rest was absorbed by carbon sinks on land and in the oceans. In the past 50 years, the fraction of CO2 emissions that remains in the atmosphere each year has likely increased, from about 40% to 45%, and models suggest that this trend was caused by a decrease in the uptake of CO2 by the carbon sinks in response to climate change and variability. Changes in the CO2 sinks are highly uncertain, but they could have a significant influence on future atmospheric CO2 levels. It is therefore crucial to reduce the uncertainties